[meteorite-list] Telescope Tracking Asteroids (LINEAR)
From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Thu Apr 22 10:32:52 2004
Telescope tracking asteroids
Watch at White Sands would provide warning of object approaching Earth
By Sue Vorenberg
Albuquerque Tribune (New Mexico)
March 19, 2004
Tucked away on the corner of White Sands Missile Range is a telescope
that's found more than 50 percent of all known asteroids, its operators
If the sky were to start falling - in the form of a giant asteroid
crashing into the Earth - that telescope would almost certainly be the
first to see it. It might even give the world some advanced warning, so
scientists could find a way to prevent the destruction, said Grant Stokes,
"If you're thinking about these large objects in space what we don't want
to do is find one that's already on its way to Earth," Stokes said. "What
we want to do is find all the potential ones that could get to Earth and
catalogue them all so we'll know ahead of time."
On Monday, the telescope - operated by the Massachusetts Institute of
Technology - found a 100-foot-long asteroid that came within 26,500 miles
of Earth on Thursday afternoon. That object, called 2004 FH, will go into
a larger National Aeronautics and Space Administration database of
near-earth asteroids. NASA hopes to complete the database in 2008, Stokes
"In elementary school we learn that the solar system is a very pristine
place, with planets circling the sun," Stokes said. "In reality it's a
very messy place, with a lot of material floating around. Asteroids are
common, but it's not the first thing I worry about in the morning. The
Earth is small and the solar system is very big. Impacts are actually
The 2004 FH asteroid is the closest near-miss object that astronomers
have ever seen, Stokes said.
"Smaller objects hit the Earth all the time, but this is large enough to
pay attention to," he said. "If it hit it wouldn't hurt the entire planet,
but it would cause significant local damage."
If the object hit Earth it could level about 100 square miles of forest,
much like the famous Tunguska impact of 1908, which leveled a similar
amount of terrain in Siberia.
The university chose to put the telescope in New Mexico because of the
state's famous dark skies, said Roger Sudbury, a scientist at Lincoln
Laboratories, the MIT-owned facility that operates the telescope.
"You get a lot of good observation nights in New Mexico," Sudbury said.
"Our site isn't at high altitude like many telescopes are, but there
aren't many rainy nights and there isn't much ambient light there. It's
a good site for observation."
Both Sudbury and Stokes split time in Massachusetts and New Mexico, they
MIT originally designed the telescope, built in 1998, for the Air Force
to detect satellites. NASA started using it a few years ago as part of
its Near Earth Object Program, Stokes said.
"We find about 70 percent of all new asteroids each year," he said.
"There's probably about 100,000 objects flying around that are about
this size that could get close to Earth."
The MIT device - the Lincoln Near Earth Asteroid Research (LINEAR)
telescope - is different from other telescopes in the way its mirror
is shaped and in how it looks at objects, Sudbury said.
"In some ways it works a lot like a digital camera," he said. "What we
do with it is record multiple images over time. While we do that, we
register stars in the background. Any objects we find that move between
those stars are likely either satellites or asteroids."
Using the technology to map out asteroids could one day save lives, Stokes
"It's a real international resource," Stokes said. "The data we take in
New Mexico provides the science community with a unique set of data that
the whole world uses. It helps lots of people."
Received on Mon 22 Mar 2004 12:37:34 PM PST